Fingerprinting is a way to identify a person by fingerprints. Papillary pattern

The search for criminals and the establishment of their involvement in one or another criminal act is the primary task of the police departments of all countries of the world. Fingerprints, the so-called papillary pattern, are used as the undisputed evidence of the suspect’s guilt. As you know, the probability of meeting people with the same lines is simply negligible. But how do we know that? This helps us a special scientific discipline - fingerprinting. This is the very section of criminology, which is nowadays considered the main and most important to study. It is about him that our conversation will go today.

What is fingerprinting?

Modern forensic science is quite difficult to imagine without this science, and even harder to understand how the police of the eighteenth and nineteenth centuries conducted investigation of crimes without having a fingerprint base.After all, dactyloscopy is a method of identifying a person’s personality, which uses the individuality of the impressions of his fingers and palms.

At the moment, forensic science is based on this method, all the fingerprint laboratories in the world work using identical technology. Although we can say that this science is one of the youngest and least studied. Yes, the method referred to in all courts refers to scientifically unverified. How could this happen? Now we will tell you everything in detail.

The history of fingerprinting

In fact, people have always had an idea that the patterns on the fingertips are different for each person. This was given a mystical significance and used for their own purposes in Babylon and China. It was believed that if a person put a fingerprint under any document, then he simply must comply with the terms of the contract. Although classify papillary pattern then no one has yet occurred to me.

Many consider the founder of the fingerprinting of the Englishman William Herschel. At the end of the nineteenth century, he worked in India and was constantly faced with cases of fraud in the design of financial papers.The fact is that most Indians were illiterate people and put a squiggle under the treaties. However, they did not consider themselves obligated to fulfill their obligations. Therefore, Herschel, recalling the mystical significance of handprints for Indians, introduced the condition of leaving a print under the contract. Surprisingly, the method worked, and Herschel received one hundred percent compliance with the rules and conditions specified in the document. During his work, the Englishman noticed that each print is different from the other and no two are alike.

With the help of the same prints, William saved himself from constant shortages in the payment of wages to the soldiers, who also sent their relatives for money and thus received double or even triple wages. After Herschel ordered them to leave fingerprints on the list, the situation returned to normal. All this is very interested in the Englishman, who began to seriously study the various prints of hands. The greater the base he had accumulated, the more he was convinced how individual the patterns on the hands of man.

The inquisitive Englishman even took the prints of criminals in a local prison and brought order there.Indeed, previously many offenses remained unpunished because of the inability of Europeans to distinguish between Indians by persons. As soon as the process of investigation began to pay attention to fingerprints, the problem resolved itself. We can say that fingerprinting was born at this very moment.

Development of fingerprinting

In fairness it should be said that not only Herschel undertook to study the fingerprints of various people. In parallel, he worked on this new method a few more people. For example, one of the talented Scottish doctors G. Folds quite accidentally noticed fingerprints on the clay products of Japanese masters. He became interested in these drawings and set out to find out how diverse they are and whether they can change throughout life. He took prints from his patients, servants and just acquaintances. To his great surprise, they never recur. In addition, ideally coincided with the traces left on the glass or any other polished surface. These observations even inspired him to a scientific article, which, however, did not attract the attention of the public.

Not the last role in the development of fingerprinting belongs to policeman Bertillon. He ordered his staff to fingerprint all detainees and suspects. As a result, he gathered an extensive card file, which helped in the detection of many crimes. This was the first time in history when fingerprinting in forensic science proved to be a justified and useful method of personal identification.

Classification of papillary patterns

Over time, the base fingerprints, taken as an experiment, accumulated in many police stations, but no one knew how to classify them. In the nineties of the nineteenth century, Charles Darwin’s brother tried to combine all the known designs of various people and classify the patterns on his fingers. Francis Galton applied the foundations of higher mathematics in his research and managed to deduce that the probability of a coincidence of papillary patterns is one chance for sixty-four billion. It was just an incredible number at the time.

Galton's classification had some flaws, but still was the first serious scientific work on this topic.The researcher identified four types of papillary lines:

with triangles;

without triangle;

right triangle;

the triangle on the left.

The card index collected as a result of this classification was unevenly filled. Therefore, a new, more efficient way was needed that could be used by the police. On the basis of his works, Galton released a whole book, where he honestly pointed out all the people whose work he used.

Edward Henry, who serves the Indian police, took advantage of Galton’s book to create his own fingerprint classification system, which modern fingerprinting uses. It was a huge breakthrough in science and forensics. Henry's developments served as the basis for the work of the police in British India and immediately several times increased the efficiency and effectiveness of such a difficult matter as the investigation of crimes.

Henry divided the patterns into the following types:

arc (simple and fir-shaped);

loops (radial and ulnar);

swirls.

In addition, Henry identified the delta, called the Galton triangle, and divided the pattern into several subspecies.The researcher derived a number of formulas, thanks to which it was possible to effectively and accurately identify a person by fingerprints.

The first application of the new methodology in forensics

For the first time, fingerprinting was applied in the trial of the Stratton brothers. They were accused of double murder, and the main evidence was a bloody imprint of one finger. Checking the match, the police found similarity on eleven points. This was quite enough to convict sentenced to hang. Surprisingly, the judge categorically disagreed with this decision, although he was forced to agree with the jury.

The use of this methodology in litigation as an evidence base caused a squall of public criticism. First of all, an exposing article was published by Folds, the same doctor who worked on the study of fingerprints. The fact is that Folds referred to some “rawness” of the method. He tried to explain that for many people the patterns on the fingers are quite similar, and the differences are expressed in just a few papillary lines.These differences can only be seen by taking fingerprints in the laboratory. Otherwise, experts may make a mistake.

In addition, Folds was frightened that the accuracy of the method was absolutely not in doubt. Everywhere judges, jurors, police and lawyers argued that fingerprinting is the only science that guarantees one hundred percent correct result. It never occurred to anyone to study science, and quite illiterate at that time police officers used technology very carelessly. Nevertheless, forensic science has already realized the convenience of the new method, and it began to be used throughout the world.

Scientific fundamentals of fingerprinting

What is the basis of fingerprinting in reality? Why are absolutely all people on the planet so confident in this method? Let's try to figure it out.

In fact, serious scientific work on fingerprints is not so much. What is the scientific rationale for fingerprinting? Specialists count only two of them:

no identical fingerprints have yet been encountered in any database or file cabinet, even a computer program does not find such coincidences;

patterns on the fingers of identical twins are not identical.

These two facts were enough to turn fingerprinting into an exact science. In fact, over time, experts have more questions for her. For example, twenty years ago, an FBI agent sent fingerprint letters to the American laboratories and fingerprints of a suspect. What was his surprise when the labs gave completely different results. This significantly shaken faith in fingerprinting.

Recently, it was reported that fingerprints may change over the course of a lifetime. Previously, such facts were not available to forensic scientists, so at the moment there are all the prerequisites for not taking the results of fingerprinting as one hundred percent proof of the guilt of the suspect.

Can you fool nature?

As soon as fingerprinting began to be used everywhere, the bandits thought about the possibility of deceiving nature, in particular changing fingerprints. The first to try to do this in the thirties of the last century were American gangsters.The members of one of the gangs with the help of a surgeon cut off the skin from their fingers and hoped that they completely got rid of past imprints. But after some time the wounds healed, and the old drawings appeared again.

Then came John Dillinger. This famous gangster in all states burned his skin with acid, making the finger pads absolutely smooth. This method also proved to be ineffective - after a couple of months papillary lines began to appear on the fingers.

In the thirty-fourth year of the last century, FBI agents encountered a new attempt to avoid retaliation for their crimes. The police found the corpse of a famous gangster, but the fingerprinting of the hands testified that there was a completely different person in front of them. The summoned agents examined the hands of the deceased and found numerous small cuts on them. As it turned out, the criminal tried to confuse the investigation with a framing. But even such a radical method did not bring the desired result, later it was proved that over the cuts, the papillary lines will again appear after a while.

After these futile attempts to deceive the nature of the criminals have ceased to conduct radical experiments on their own hands.

What is used to detect fingerprints at a crime scene?

In modern forensic science uses several methods for determining fingerprints. Most often, experts use the following aids:

dactyloscopic powder;

fluorescent powder;

iodine pairs.

Of course, there are others, at the moment there are more than twelve known tools that allow you to take prints from different surfaces. The choice of technology by an expert depends on them.

Where are fingerprints stored?

Forensic experts are well aware of the term “fingerprint card”. These cards are the basis of the database of papillary patterns. Usually it contains the personal data of the suspect and the fingerprints of each finger along with the palms. Each print should be extremely clear and understandable, on the reverse side there is a criminal article, on which the charge is made.

The fingerprint card must also contain the date of the procedure and the data of the person who takes the prints.

Fingerprint examination: details

The purpose of the fingerprint examination is under the authority of the investigators. Under the law, they may take fingerprints and handwriting samples from suspects. All these actions are carried out in the interests of the investigation in order to identify the person.

Fingerprinting is a fairly simple and straightforward process. Ink is applied to clean and dry hands with a roller. Further, if the investigator rolls the fingertips over the fingerprint card, after receiving all the prints, the paint can be washed off with warm water and soap. Now in large cities it is becoming quite common to take fingerprints with the help of modern technical means. A special device scans finger pads and immediately creates an electronic fingerprint card in the database. This excludes minor inaccuracies and errors.

Universal fingerprinting: myth or reality

In recent years, information about universal fingerprinting is now and again found in the media. This idea periodically arises in the minds of governments of different countries. And for the first time this idea arose in the nineteenth century in England and has not yet been realized in any country of the world. After all, this proposal causes many disputes among ordinary citizens. On the one hand, it will be easier to investigate crimes, and on the other hand, it violates personal human rights. Ultimately, universal fingerprinting remains the only possible method out of many others,allowing in case of use to reduce the level of world crime.